ZOOLOGISCHE MEDEDELINGEN
UITGEGEVEN DOOR HET
RIJKSMUSEUM VAN NATUURLIJKE HISTORIE TE LEIDEN (MINISTERIE VAN WELZIJN, VOLKSGEZONDHEID EN CULTUUR)
Deel 58 no. 6 11 juli 1984 ISSN 0024-0672
A NEW GENUS AND TWO NEW SPECIES OF MINUTE LEPTODACTYLID FROGS FROM NORTHERN SOUTH AMERICA, WITH COMMENTS UPON PHYZELAPHRYNE (AMPHIBIA: ANURA: LEPTODACTYLIDAE)
by
MARINUS S. HOOGMOED
and
JEAN LESCURE
Hoogmoed, M. S., & J. Lescure: A new genus and two new species of minute leptodactylid frogs from northern South America, with comments upon Phyzelaphryne (Amphibia: Anura: Leptodactylidae). Zool. Med. Leiden 58 (6), 1 l-vii-1984: 85-115, figs. 1- 11, tables 1-3. — ISSN 0024-0672. Key words: Anura; Leptodactylidae; genera; Adelophryne gen. nov.; Eleutherodactylus; Phy• zelaphryne; key; Neotropics. The synonymisation of Phyzelaphryne miriamae Heyer with Eleutherodactylus nigrovittatus An- dersson is denied and it is shown that both species are quite distinct in numerous characters. A new genus (Adelophryne) of minute leptodactylid frogs with pointed discs on the toes and a dis• tinctly reduced fourth finger, containing two new species (A. adiastola spec. nov. and A. gutturosa spec. nov.) is described from northern South America. A key to separate the diminutive leptodac• tylid frogs with pointed toetips is given. The relationships of the new genus are not clear, but possibly are with one of the species groups of Eleutherodactylus, of the subfamily Eleutherodacty- linae. M. S. Hoogmoed, Rijksmuseum van Natuurlijke Historie, P.O. Box 9517, 2300 RA Leiden, The Netherlands. J. Lescure, Muséum Nationale d'Histoire Naturelle, Reptiles et Amphibiens, 25, Rue Cuvier, 75005 Paris, France.
RESUMEN
Se niega la sinonimisación de Phyzelaphryne miriamae Heyer con Eleutherodactylus nigrovitta• tus Andersson y se muestra que las dos espécies son bastante distincta en numerosas característi• cas. Se describe un nuevo genero (Adelophryne) de ranas leptodactylidos menudas con discos
85 86 ZOOLOGISCHE MEDEDELINGEN 58 (1984) puntiagudos en los dedos del pie y con el dedo cuarto del mano reducido, conteniendo dos espé• cies nuevas (A. adiastola spec. nov. y A. gutturosaspec .nov. ) del norte de America del Sur. Se présenta una clave para la distinction de las espécies pequenas de ranas leptodactylidos con dedos del pie puntiagudos. Las relaciones del género nuevo no son claro, pero tal vez son con uno de los grupos de espécies de Eleutherodactylus, de los Eleutherodactylinos.
SOMMAIRE
La mise en synonymie de Phyzelaphryne miriamae Heyer avec Eleutherodactylus nigrovittatus Andersson n'est pas valable car de nombreux caractères distinguent vraiment les deux espèces. Adelophryne, un nouveau genre de très petits Leptodactylidés, identifiable par des disques poin• tus à l'extrémité des orteils et un quatrième doigt nettement réduit, et ses deux espèces originiai- res du nord de l'Amérique du Sud, A. adiastola spec. nov. et A. gutturosa spec, nov., sont décrites. Une clé est établie pour différencier les petits Leptodactylidés qui ont l'extrémité des orteils poin• tue. Adelophryne est à notre avis un Eleutherodactyliné, mais ses relations avec les autres genres de cette sous-famille ne sont pas encore claires.
INTRODUCTION
From Amazonian South America several small species of leptodactylid frogs have been described recently. These species, though probably not direct• ly related, agree in being very small, having pointed tips of fingers and toes, lacking webbing between the toes, and probably share the same type of habi• tat, viz., leaf-litter. Lynch (1976) described two species from eastern Ecuador and northeastern Peru, which he considered belonging to the genus Euparkerella, otherwise only known from the species E. brasiliensis (Parker) from southeastern Brazil. The two new species (E. lochites and E. myrmecoides) differ from E. brasilien• sis in their more slender habitus, in having a middle ear, in having an inner tarsal tubercle, in having a proportionally longer fifth toe and in being smaller and more slender. Lynch (1976) considered the fact that the three species agreed with each other in having lost one phalanx in the fourth finger, in the condition of the palate and in the arrangement of skull bones, more important than the differences mentioned before and consequently considered them congeneric. Hey er (1977), on the occasion of the study of a collection of frogs from the Rio Madeira, evaluated the relationships between Barycholos, a few species of Eleutherodactylus (among which E. nigrovittatus Andersson), Euparkerella brasiliensis, E. myrmecoides and some specimens of a new frog species. On the basis of his analysis he came to the conclusion that the supposed relationship between E. brasiliensis and E. myrmecoides was based upon characters of loss HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 87 and therefore was suspect. He came to the conclusion that they only shared two derived character states, but differed in eight others. According to Heyer (1977) the shared characters could be consequences of small size and the char• acters separating them could reflect a functional feeding shift in E. brasiliensis and a functional locomotory shift in E. myrmecoides. These data induced Heyer to erect the new genus Phyllonastes in order to accomodate the two species myrmecoides and lochites. He ascribed the similarities largely to "con• vergent adaptations to the leaf litter habitat". Another result of his evaluation was that he described the specimens of his new frog in the new genus Phyze• laphryne under the specific name P. miriamae. The genus and species are a.o. distinguished by having terminal digital papillae, distinct vomerine teeth, a single subarticular tubercle under the fourth finger and three phalanges in the fourth finger. Apart from the holotype and the three topotypic paratypes Heyer (1977) studied four additional frogs from the Vaupés River. Because of differences which he attributed to sexual dimorphism, but of which he also said they could represent differentiation at the species level, he excluded these four spe• cimens from the type-series. Lynch (1980b) considered P. miriamae conspecific with Eleutherodactylus nigrovittatus and in this decision was followed by Lynch & Lescure (1980). From the text it appears that Lynch (1980b) did not study the holotype, nor any of the paratypes of P. miriamae, but solely based his decision on the des• cription and illustration of P. miriamae. According to Lynch (1980b), Heyer (1977) wrongly stated than the distal subarticular tubercle under finger IV of P. miriamae was lost and he attributed this to the fact that the proximal subar• ticular tubercles of fingers III and IV in E. nigrovittatus are relatively large and more distinct than the distal tubercles under these fingers. Our re-exami• nation of all type-material of P. miriamae and direct comparison of it with fresh specimens of E. nigrovittatus leads us to disagree with Lynch and to reinstate the genus Phyzelaphryne. Small specimens of frogs, apparently adult, from Roraima and Serra do Navio instigated the present study. Initially we arranged the specimens in the genus Euparkerella as defined by Lynch (1976), buth Heyer's (1977) article prompted us to reconsider our former opinion. Direct comparison of these specimens with the paratypes of P. miriamae and with the Vaupés specimens mentioned by Heyer (1977) convinced us that the Vaupés specimens were differ• ent from the types of P. miriamae and together with the new material formed a new genus, containing two species. 88 ZOOLOGISCHE MEDEDELINGEN 58 (1984)
SPECIES ACCOUNTS
Phyzelaphryne miriamae Heyer, 1977 (figs. 1,3, 4, 11)
Phyzelaphryne miriamae Heyer, 1977: 153. Eleutherodactylus nigrovittatus: Lynch, 1980b: 301 (partly); Lynch & Lescure, 1980: 311 (partly); Harding, 1983: 272. Material of P. miriamae. — 19, MZUSP 49894 (holotype), Igarapé Puruzinho, Rio Madeira, Amazonas, Brazil, 5xi1975, leg. M. H. and W. R. Heyer, F. do Val, P. E. Vanzolini; 2 9, 1 ο*, USNM 2026078, MZUSP 49895 (paratypes), as holotype, but 5/6xii1975; 1 o*, USNM 239363, Parque Rio Tapajós, 75 km SW of Itaituba, Pará, Brazil, 20Í1979, leg. R. I. Crombie; 1 ex., DZUB not registered, Humaita, Rio Madeira, Amazonas, Brazil, 9iii1975, leg. U. Carama schi. Comparative material of E. nigrovittatus. — Peru. Depto. Loreto. Colónia: 19, 2â, ΜΝΗΝΡ 19782839, 2844, 2845, JanuaryMarch 1978, leg. P. Razon; 1 ο*, MNHNP 19782840, 30V1978, leg. J. Lescure; 1 9, 3d, MNHNP 19782841, 2842, 2843, 2846, 12/14vi1978, leg. J. Lescure. Ecuador. Napo Province. Loreto: 1 9, RMNH 21638, leg. J. Olalla. Pastaza Province. Shiona: 1 9,2 ex., RMNH 2163941, 26iv1983, 2 9, RMNH 216434, 13viii1983, 1 o*, RMNH 21645, 14viii1983, all leg. M. S. Hoogmoed & A. Almendariz. Montalvo: 1 hgr., RMNH 21646, 16viii 1983, leg. M. S. Hoogmoed & A. Almendariz. Pozo Huito, 85 km E. Montalvo: 1 9, RMNH 21642, 22ÍV1983, leg. M. S. Hoogmoed & A. Almendariz. Comparative material of Phyllonastes myrmecoides. — Peru. Dpto. Loreto. Colónia: 2 9, MNHNP 19797898/9, January April 1978, leg. P. Razon. Brazil. Amazonas. Igarapé Belém (near Rio Solimoes), ± 70 km E. Letícia: 2 9,1 o*, ΑΜΝΗ 9705052, 18/28V1970, leg. Β. Malkin. These two localities extend the known range of this species, so far only reported from the sur roundings of Iquitos, about 400 km to the east.
Description. — The description given by Heyer (1977: 153154) of this spe cies mostly is correct, but needs some additions and/or corrections on several points. In the following account only those characters are mentioned in which we noticed differences with Heyer's description. In lateral profile the snout is truncate to rounded. Loreal region nearly ver tical, slightly concave. When viewed from above, the eyes project beyond the circumference of the head (fig. 1). The tympanic annulus is complete. There is an oblique glandular ridge from some distance below the tympanum (not in contact with the tympanic annulus) to the insertion of the forelimb (fig. 1). Dorsal and lateral surfaces not granular, but shagreened. The tongue has a short narrow stem, which widens into a large subcircular head, free over its entire length. Vomerine teeth ca. 10. The relative length of the fingers de pends on the method used at measuring. When the fingers are pressed against each other, the second finger is slightly longer than the first, when measured from the base of the corresponding basal subarticular tubercle, they are of equal length. Thus, Heyer's formula is correct, but should be interpreted ac HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 89 cording to the above statement. The fourth finger has three phalanges, of which the second one is rectangular. The small discs on top of fingers III and IV are pointed, with shallow lateral grooves, which are interrupted at the tip. Tips of fingers I and II hardly expanded into discs, pointed, without lateral grooves. The metacarpal tubercles oval, three additional palmar tubercles (fig. 3a). Discs of toes deeply grooved laterally, narrowly interrupted at the pointed tip. Subarticular tubercles of both fingers and toes well developed, salient. Fingers I-V with respectively, one, one, two and one tubercles, toes I-IV with respectively, one, one, two, three and two tubercles. Both fingers and toes round in cross-section. Inner metatarsal tubercle oval, no additional solar or tarsal tubercles (fig. 3b). There is a white subtympanic stripe from below the eye to the insertion of the arm, which in its posterior part coincides with the glandular subtympanic ridge. An indistinct, narrow, interrupted darker verte• bral stripe. Colour in life of male USNM 239363 (field notes of R. I. Crombie): "Above yellowish brown, becoming grayish on head and more chestnut on rump. Suggestion of yellow on sides, in groin and on thighs. Indistinct grayish lateral line from eye to just past axilla; darker one from naris-eye. Belly gray with distinct white spots." The "fourth paratype" mentioned by Heyer (1977: 154) as having a snout- vent length of 14.6 mm and surmised to be a juvenile female, in our opinion is a male (MZUSP 49895). It has vocal slits and a subgular vocal sac which is indicated by longitudinal folds in the posterior part of the throat. The throat also is darker than in the females. According to measurements by MSH in 1981 the snoutvent length of this specimen is 15.1 mm (see table 2). Discussion. — In our opinion the generic definition should include a state• ment about the number of phalanges in the fingers (2-2-3-3) and that in the toes (2-2-3-4-3) and it also should be made clear that the terminal phalanges of both fingers and toes are T-shaped. The well defined, oblique subtympanic gland, not in contact with the tympanic annulus (complete), should also be included. From our study of the types (MZUSP 49894-5, USNM 202607-8) of P. miriamae it became clear to us that Heyer (1977) was correct in assigning this taxon to a new genus and that Lynch's (1980b) conclusion that P. miria• mae is synonymous with Eleutherodactylus nigrovittatus is wrong, because it is not substantiated by our findings. As stated above, we strongly suspect that Lynch (1980b), being convinced of his right interpretation, did not study the type-specimens of P. mariamae and only based himself on the published ac• count and illustration. On this evidence, he brushed aside Heyer's (1977) ob• servation that under the fourth finger only a single subarticular tubercle was present and implied that this was based on defective observation on Heyer's 90 ZOOLOGISCHE MEDEDELINGEN 58 (1984)
Fig. 1. Phyzelaphryne miriamae (USNM 202608). Dorsal (upper) and lateral (lower) view of head. The bar represents 1 mm. HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 91
Fig. 2. Eleutherodactylus nigrovittatus (RMNH 21642). Dorsal (upper) and lateral (lower) view of head. The bar represents 1 mm. 92 ZOOLOGISCHE MEDEDELINGEN 58 (1984) part. Our recent examination of the types of P. miriamae completely corrobo• rates Heyer's observation that there is only a single, well developed subarticu• lar tubercle under the fourth finger. As P. miriamae has three phalanges in the fourth finger, in combination with a single subarticular tubercle, this observa• tion is in contradiction with Lynch's (1976) statement that loss of a phalange in leptodactylid frogs is accompanied by loss of a corresponding subarticular tubercle. As Heyer (1977) correctly concluded, P. miriamae shows "that a shortening of the digit, reflected by loss of a subarticular tubercle need not be necessarily accompanied by a loss of a skeletal element". Lynch's (1980b) statement about the configuration of subarticular tubercles in Eleutherodactylus nigrovittatus is correct and we could ascertain it with the material at our disposition (part of which (MNHP 1978—2839/46) was also examined and identified as such by Lynch & Lescure (1980)). However, com• parison of figs. 3a and 3c will make clear that they represent completely dif• ferent situations, which are not due to simple variation. Indeed, the distal sub• articular tubercle under the fourth finger in E. nigrovittatus (fig. 3c) is less distinct than the proximal one (fig. 3a), but still distinct enough to be observ• ed, whereas in P. miriamae this tubercle is completely absent. Another, easily observed difference between the two species is the shape of the head. In P. miriamae (fig. 1) the sides are nearly vertical, causing the eyes to project beyond the circumference of the head when viewed from above (also see fig. 2 in Heyer (1977)), whereas in E. nigrovittatus (fig. 2) the sides of the head are sloping outward, causing the eyes to fall completely within the circumference of the head (also see fig. 7 in Lynch (1980b)). Moreover, males of P. miriamae have snouts that do not differ in shape from those of the females, whereas in E. nigrovittatus the males are reminiscent of male Adenomera and have a shovel-shaped fleshy ridge on the snout (Lynch, 1980b: fig. 7). These and other differences between the two species have been tabulated in table 1 and in our opinion clearly show that we are dealing with two taxa.
Adelophryne gen. nov.
Type species: Adelophryne adiastola spec. nov. Diagnosis. — A genus of minute leptodactylid frogs, with asymmetrically pointed, laterally grooved, elongate discs, digits flattened, fourth finger re• duced in. size, having two or three phalanges and only one subarticular tuber• cle. This combination of characters distinguishes it from other small leptodac- tylids with pointed discs (Euparkerella, Phyllonastes, Phyzelaphryne, Eleutherodactylus). Adelophryne differs from Phyzelaphryne in having flat- HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 93
Fig. 3. Palmar (a, c) and plantar (b, d) surfaces of hands and feet, a, b: Phyzelaphryne miriamae (USNM 202608); c, d: Eleutherodactylus nigrovittatus (RMNH 21642). The bar represents 1 mm. 94 ZOOLOGISCHE MEDEDELINGEN 58 (1984)
tened digits, indistinct subarticular tubercles, a long and slender tongue and in showing reduction of the phanlanges in the fourth finger. From Phyllonastes and Euparkerella it differs in having vomerine teeth, in lacking a tarsal tuber• cle and in the variable number of phalanges in the fourth finger. From Eleu• therodactylus it differs in having only one subarticular tubercle under the fourth finger, and in showing a distinct reduction in size of the fourth finger. Description. — Minute (snout-vent length adults not exceeding 15 mm) leptodactylid frogs, with horizontally oval pupil, a distinct tympanum with an incomplete tympanic annulus, smooth to granular skin, a subtympanic gland• ular ridge, asymmetrically pointed, narrow, circumferentially (groove narrow• ly interrupted at the tip) grooved discs on the toes, fingers with asymmetric• ally pointed tips, indistinct subarticular tubercles, only a single one under the fourth finger, fingers and toes not webbed, smooth tarsus, small, round outer metatarsal tubercle, large, flat inner metatarsal tubercle. Males with a large, external subgular vocal sac, thumb lacking nuptial asperities. Number of pha• langes in fourth finger two or three, terminal phalanges of fingers and toes knobbed or T-shaped. Ilium without a dorsal crest. Frontoparietals meet me• dially, not exposing a fontanelle, vomerine and maxillary teeth present, occi• pital condyles widely separated, last presacral vertebra about as wide as the sacrum, sacral diapophyses rounded, distally slightly wider, omosternum with• out bony element. Etymology. — From the Greek adelos, unseen, unknown, obscure and phryne, toad, in reference to the fact that these small froglets hardly have been collected for science until recently. The genus is feminine in gender. Contents. — Two species, viz., Adelophryne gutturosa spec. nov. and A. adiastola spec. nov. Distribution. — Northern South America east of the Andes (roughly the Guiana Shield). Relationships. — It is difficult to say anything well founded regarding this topic, because the seven specimens available were not dissected to study mus• cle arrangements and the characters used are mainly external, together with a few skeletal features derived from X-ray photographs. Characters like reduc• tion of the number of subarticular tubercles under the fourth finger, and the reduction of the number of phalanges in the fourth finger are characters in• volving loss of morphological elements and accordingly provide little infor• mation in deducing relationships. A character like pointed discs on the toes probably has an adaptive value, though we are not aware what its use could be, and apparently arose independently in several groups, as the final situa• tion appears to have been realised along different routes. Although nothing is known about the mode of reproduction (amplexus, number and size of eggs, HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 95 development of eggs), judging by the size only, it seems most reasonable to suppose Adelophryne only produces few large eggs having a large vitellin re• serve which would facilitate direct or semi-direct development of the juveniles after the eggs have been deposited. This supposition seems to be strengthened by the fact that development is direct in the similarly sized Euparkerella/Phyl- lonastes (Lynch, 1976) living under corresponding circumstances. Solely based on the available morphological data this genus appears to be• long to the tribe Eleutherodactylini of the subfamily Telmatobiinae (Lynch, 1971; Dowling & Duellmann, 1974-1978) or to the subfamily Eleutherodacty- linae as defined by Laurent (in press) after Lutz (1954). For a key to the known species of Adelophryne, we refer to the fifth couplet of the general key at the end of this paper.
Fig. 4. Radiographs of hands of small eleutherodactyline frogs, a. Phyllonastes myrmecoides, b. Phyzelaphryne miriamae, c. Eleutherodactylus nigrovittatus, d. Adelophryne adiastola, e. A. gutturosa. The pictures are not to scale and only serve to show the different arrangements of phalanges.
Adelophryne adiastola spec. nov. (figs. 4, 5, 6, 7,11)
Phyzelaphryne miriamae Heyer, 1977: 154 (partly, referred material only).
Holotype. — o*, UTACV 4943, Yapima, Vaupés River, Vaupés, Colombia (69°28'W 1°03'N), 21-ÍV-1976, leg. W. F. Pyburn. Paratypes. — 1 9,2 â, UTACV 4940-42, same data as holotype.
Diagnosis. — A minute (maximum snout-vent length 13.9 mm) frog, fourth finger distinctly reduced, only having two phalanges and one indistinct subar• ticular tubercle. Fingers and toes depressed, Tips of fingers without discs, with 96 ZOOLOGISCHE MEDEDELINGEN 58 (1984) asymmetrically pointed tips. Tips of toes expanded into circumferentially grooved, asymmetrically pointed discs. Terminal phalanges of fingers bluntly pointed or T-shaped, of toes T-shaped. Skin of back shagreened to granular. Adult males with large subgular vocal sac. Description. — Snout-vent length 13.0-13.9 mm. Head longer than wide, head slightly wider than adjacent part of body. Snout rounded in dorsal, rounded to truncate in lateral profile, tip of snout round. Distance between eye and tip of snout equal to or slightly longer than the diameter of the eye. Distance between eye and nostril less than the distance between the nostrils, distance between nostril and tip of snout slightly less than 1/3 the distance between eye and tip of snout. Canthus rostralis indistinct, rounded, straight; loreal region sloping steeply to the upper lips, flat. Lips not flaring. Nostrils inferolateral of canthus rostralis, not projecting, a vertically oval opening in a round translucent area, directed laterally. Eye with horizontally oval pupil. Interorbital space more than 1.5 times as wide as an upper eyelid, slightly con• vex. Temporal region vertical; tympanum small but distinct, round, 0.3—0.4 times the diameter of the eye, surrounded by a distinct, incomplete tympanic annulus; distance between tympanum and eye slightly less than, or equal to, the tympanum diameter. A skinfold from the corner of the mouth to the lower margin of the tympanum; postero-dorsal margin of tympanum obscured by an indistinct supratympanic fold; a glandular series of warts forming an inter• rupted ridge from the tympanum to the insertion of the forelimb. Choanae medium-sized, round; pre vomerine processes present, bearing a transverse row of two to eight teeth each, posteriorly of the choanae, just ante• riorly of the palatine bones. Tongue mushroom-shaped, the capitum only slightly wider than the stem, not notched behind, completely free, except at its anterior margin. Males with long, curved vocal slits and a large, subgular vo• cal sac, extending onto the anterior part of the chest and to the insertion of the forelimbs. Skin of back and flanks granular or shagreened, skin of venter smooth, skin of throat at sides granular and wrinkled, the central area smooth, skin of limbs smooth. Discoidal folds absent. Posteroventral aspect of thighs coarsely areolate. Indistinct transverse folds of skin present on the upper surface of the wrists and on the posterior aspect of the heels. Hand with a large, undivided, flat, oval outer and a smaller, flat, oval inner metacarpal tubercle. Subarticular tubercles present, but indistinct, large, flat and oval, one under each finger, except under the third, which has two of them. A single, indistinct, flat, round supernumerary palmar tubercle at the base of the third finger. Fingers free of web, no lateral fringes, fingers not expanded into pads or discs, with an asymmetrically pointed tip, distinctly de- HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 97
Fig. 5. Adelophryne adiastola (UTACV 4943). Dorsal habitus and lateral view of left side of head. 98 ZOOLOGISCHE MEDEDELINGEN 58 (1984) pressed, without circumferential groove. Fingers: I < IV < II < III, fourth finger very small, free part less than half the free part of the third finger. Pha• langeal formula 2-2-3-2, terminal phalanges of fingers II and III T-shaped, of fingers I and IV knobbed or bluntly pointed. Tarsus smooth, without a tarsal ridge or tubercle. A large, flat, oval inner and a smaller, protruding, round outer metatarsal tubercle, approximately half the size of the inner one. Subarticular "tubercles" flat, oval, indistinct, the basal ones of toes IV and V most distinct. Tips of toes dilated into small asym• metrical discs, slightly wider than the toes, ending in an asymmetrical papilla• te point; discs with a circumferential groove which is narrowly interrupted at the tip. Toes distinctly depressed, free of webs and lateral fringes. Toes: I < II < V 1 mm Fig. 6. Adelophryne adiastola (UTACV 4943). Ventral habitus. 100 ZOOLOGISCHE MEDEDELINGEN 58 ( 1984) Fig. 7. Adelophryne adiastola (UTACV 4943). Plantar (left) and palmar (right) surfaces of right foot and hand. HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 101 characters: body proportions, skin texture, morphology of head, hands and feet, colour pattern and, as far as we could ascertain from Xray photographs, skeleton, there are no differences, we consider UTACV 4940 conspecific with the other three specimens in the typeseries and assume that there is rather extensive age variation in the characters mentioned above. Of course we can not rule out the possibility that sexually dimorphic characters are involved that have not yet expressed themselves completely, due to differences in the sexual cycle. Natural history. — Only few data are available. All specimens were collec ted in the leaf litter near streams (pers. com. W. F. Pyburn). As explained above, UTACV 4940 is a young adult male, which was caught calling among leaflitter. A sonagram and a strip chart recording of the call (at 22°C) were published by Heyer (1977: figs. 3, 4). The other two males in the typeseries have large, extended vocal sacs the adult female (UTACV 4942) has well de veloped oviducts and some rather large, white ovarian eggs. Apparently the specimens were in breeding condition. From remarks by Pyburn (1977) it might be concluded that the types were collected during the rainy season. The female had swallowed a small harvestman (Sironidae, Opilionida, Chelicerata) of a group of soil and leaf litter inhabitants. The region of Yapima is in the tropical lowland rainforest zone ("Bosque muy húmedo premontano (Transición cálida)") (I.G.A.C., 1977) of Colombia, close to the Brazilian border, in the Amazonian drainage. Etymology. — From the Greek adiastolos, not separated, confused, in refe rence to the fact that originally these specimens were referred to Phyzelaphry ne miriamae. Adelophryne gutturosa spec. nov. (figs. 4, 8, 9, 10, 11) Euparkerella sp. "A" Hoogmoed, 1979: 269. Holotype. — (J, BM 1983. 1139, between camp IV and V, northern slopes of Mount Rorai ma, Guyana (60°46'W 5°17'N), 3000 feet (914 m), 26viii1971, leg. A. N. Warren. Paratypes. — 1 $ , 1 juv., LACM 442778, Serra do Veado, Serra do Navio, hills Ε. of mines, Território Amapá, Brazil (52°5'W 1°N), 300 m, vii1968, leg. P.A. Silverstone. Diagnosis. — A minute (maximum snoutvent length 14.5 mm) frog, with a slightly reduced fourth finger, having three phalanges and one indistinct sub articular tubercle. Fingers and toes depressed. Tips of fingers without discs, with asymmetrically pointed tips. Tips of toes expanded into circumferentially grooved, asymmetrically pointed discs. Terminal phalanges of fingers and 102 ZOOLOGISCHE MEDEDELINGEN 58 (1984) toes bluntly pointed, knobbed or T-shaped. Skin of back smooth. Adult males with large subgular vocal sac. Description. — Snout-vent length adults 13-14.5 mm. Head slightly longer than wide, slightly wider than adjacent part of body. Snout truncate in dorsal and lateral profile, tip of snout with an obtuse median point. Distance be• tween eye and tip of snout equal to the diameter of the eye, distance between eye and nostril about twice the distance between nostril and tip of snout. Can- thus rostralis indistinct, rounded, straight; loreal region sloping steeply to the upper lips, flat. Lips not flaring. Nostrils inferolateral of canthus rostralis, not projecting, forming a vertical oval opening in a round, translucent area, directed laterally, internarial distance slightly less than interorbital distance. Eye with horizontally oval pupil. Interorbital space 1.5 times as wide as an upper eye• lid, slightly convex. Temporal region vertical, tympanum small but distinct, round, 1/3 the diameter of the eye, surrounded by a distinct, incomplete tym• panic annulus, which is obscured by skin in its upper part; distance between tympanum and eye equals the tympanic diameter. No supratympanic fold in the male, a horizontal one present in the female; a skin fold from the corner of the mouth to the underside of the tympanum and a glandular ridge (6) or series of pustules (9 ) from the tympanum to the insertion of the forelimb. Choanae medium-sized, round; pre vomerine processes present, each bea• ring four to six teeth in the male, indistinct, with two teeth per process in the female, placed in long transverse rows, posteriorly of the choanae, just ante• riorly of the palatine bones. Tongue ribbon-like, with slightly expanded poste• rior part, not notched behind, completely free, except its anterior margin. Male with long, slightly curved vocal slits, flanking the tongue, and a large subgular vocal sac, extending onto the anterior part of the chest and to the insertion of the forelimbs. Skin of back and venter smooth, skin of throat in male wrinkled. Skin of limbs smooth, posteroventral aspect of thighs coarsely areolate. Discoidal folds absent. Hand with a large, undivided, irregularly shaped, flat, outer and a smaller, oval, flat inner metacarpal tubercle. Subarticular tubercles present, though flat and indistinct, large, oval, one under each finger, except under the third, which has two tubercles. Three indistinct, flat, oval supernumerary palmar tu• bercles, one each at the base of fingers II, III and IV. Fingers depressed, free of web, narrow, transparent lateral fringes present. Tips of fingers ending in an asymmetrically pointed tip, no discs, no circumferential groove. Fingers: I < II < IV < III, fourth finger short, free part more than half the free part of the third finger. Phalangeal formula 2-2-3-3, the second phalange in the fourth finger cubic (9) or a short rectangle (cT), terminal phalanges of fin- HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 103 Fig. 8. Adelophryne gutturosa (BM 1983.1139). Dorsal habitus and lateral view of left side of head. 104 ZOOLOGISCHE MEDEDELINGEN 58 (1984) 1mm Fig. 9. Adelophryne gutturosa (BM 1983.1139). Ventral habitus. HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 105 gers I, II and IV bluntly pointed to knobbed, of finger III knobbed ( 6 ) or T-shaped ( 9 ). Tarsus smooth, without tarsal ridge or tubercle. A large, distinct, oval, flat inner and a smaller, distinct, round, conical outer metatarsal tubercle, approx• imately half the size of the inner one. Subarticular tubercles flat, oval, indis• tinct, but more prominent than those on hands. No supernumerary tubercles. Toes depressed, free of web, narrow, transparent lateral fringes present. Tips of toes dilated into small, narrow discs, slightly wider than the toes, ending in an asymmetrically pointed tip. Discs with a circumferential groove, which is narrowly interrupted at the tip. Toes I < II Fig. 10. Adelophryne gutturosa (BM 1983.1139). Plantar (left) and palmar (right) surfaces of right foot and hand. HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 107 Guianan lowland endemic by Hoogmoed (1979: 269) under the name Eupar- kerella sp. "A". The two widely separated localities from which it is now known (fig. 11) do not alter this opinion on its distribution and status. At pre• sent it is known from altitudes between 300 and 914 m on the Guianan Shield. Etymology. — From the Latin gutturosus, with enlarged throat, in reference to the gigantic subgular vocal sac in adult males. Fig. 11. Map of northern South America, showing the known distribution of four species of small eleutherodactyline frogs here discussed. Adelophryne gutturosa (asterisks): 1. Northern slopes of Mount Roraima, 2. Serra do Veado, Serra do Navio; A. adiastola (square): 3. Yapima; Phyllonastes myrmecoides (triangles): 4. Colonia, 5. Mishana, 6. Centro Union, 7. Igarape Belem; Phyzelaphryne miriamae (dots): 8. Parque Rio Tapajos, SW of Itaituba, 9. Igarape Puruzinho, 10. Humaita. Localities for Eleutherodactylus nigrovittatus are not listed, because they fall completely within the known range of the species (Lynch, 1980a). DISCUSSION The papers by Heyer (1977), Lynch (1976, 1980b), Lynch & Lescure (1980) and the present one, all focus attention on the fact that the Amazonian area still hides a wealth of undescribed small to minute leptodactylid frogs. Some 108 ZOOLOGISCHE MEDEDELINGEN 58 (1984) of these may already have been collected and are waiting in museum collec• tions to be discovered among samples of 'juvenile' frogs. Others will turn up only through specialised fieldwork. These species apparently are largely re• stricted to leaf litter and possibly also to the superficial soil layer at the base of trees, where the soil is penetrated by roots, or at the base of rocks where cracks and fissures provide good hiding places. These habitats are difficult to sample and this probably explains the paucity of these froglets in older collec• tions, most of which have been made by non-herpetologists. Only when spe• cialised herpetologists started sampling the forest floor herpetozoan com• munities, some of these species became known to science (Phyllonastes lochi- tes due to the work of J. E. Simmons, P. myrmecoides due to that of P. Soini and J. R. Dixon, Phyzelaphryne miriamae due to that of W. R. Heyer, Ade• lophryne adiastola due to that of W. F. Pyburn and A. gutturosa through the efforts of A. N. Warren and P. A. Silverstone). Another source for new species was provided by old collections (e.g. Barycholos savagei Lynch was found mis- identified as Eleutherodactylus binotatus (Spix) and E. conspicillatus (Gün• ther)) when studied by specialists (Lynch, 1980b). The fact that these small species here are mentioned in one breath does not imply close relationship, on the contrary, we strongly suspect that a number of leptodactyline and eleutherodactyline frogs independently evolved small body size and adapted to life in leaf litter and in fissures and cracks in the soil, into which they probably slide, as they donot seem to be built for digging and might lack the strength for it. We are more inclined to consider them to be• long to the interstitial soil macrofauna, rather than just another group of leaf litter dwelling species. Their capture in leaf litter (apparently always during rainy seasons when there is a lot of water around) may have been due to acci• dental circumstances, like high groundwater table, flooding, or heavy rainfall. In general habitus they do resemble some of the smaller microhylids that can be found in the same general habitat, though these have a specialised diet of ants and termites. There are no indications that a comparable specialisation for prey evolved in these small leptodactylids and it therefore remains open to debate whether they compete with (micro)sympatric small microhylids. The find of a harvest-man in the stomach of one Adelophryne adiastola seems to indicate that they either specialised in a different direction, or have a much broader food-spectrum, a.o. harvest-men, ants, termites and other micro-in• vertebrates. It is remarkable, though, that they all evolved pointed discs on the toes and pointed fingertips, which are or are not expanded into small discs. The digit tips in all genera concerned are different and seem to have evolved independently. Eleutherodactylus nigrovittatus e.g. has small, swollen, subtriangular discs on the toes with deep, uninterrupted circumferential HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 109 grooves, while on the fingers the discs are small, not swollen, circumferentially grooved and pointed (III) or bluntly pointed. Phyllonastes on the toes has elongate, distinctly swollen, circumferentially grooved discs with a protracted papilla, placed slightly asymmetrically below the groove, while the fingers do not bear discs and the tips are slightly swollen, rounded to bluntly pointed (asymmetrically). Phyzelaphryne, on the toes, has enlarged, swollen, laterally grooved (interrupted at the tip) discs which are bluntly pointed, the tip slight• ly asymmetrical, while on the fingers the discs are small, swollen, laterally grooved (interrupted at the tip), bluntly pointed with the tip slightly asymmet• rical. Adelophryne, on the toes, has very narrow discs, with a distinctly asym• metrical tip, formed by a papilla and with a horizontal groove that passes through the tip and is interrupted there, while the fingers are strongly asym• metrically pointed, without discs. The situation found in Phyzelaphryne and Adelophryne, where the toe discs show lateral grooves which are not connected with each other because of an interruption at the tip is very similar and might reflect true phylogenetic rela• tionship. The situation found in Phyllonastes is completely different and must have been attained along quite a different route. It seems unlikely that the situation of two separated lateral grooves evolved from that in Eleutherodacty• lus, which has a transverse groove across the tip of the digital pad (Lynch, 1971). It seems more likely that the situation, as found in Phyzelaphryne and Adelophryne, evolved from species with swollen digit tips, such as are found, for instance, in some species of Adenomera (Heyer, 1973), in Barycholos (Heyer, 1969; Lynch, 1980b) and in Vanzolinius (Heyer, 1974). This compari• son does not imply direct relationship, two of the three genera mentioned (Adenomera, Vanzolinius) being considered to belong to another subfamily, the Leptodactylinae (purportedly characterised by the possession of a bony element in the sternum (Lynch, 1971, 1980b)), than Phyzelaphryne and Ade• lophryne. Until recently Barycholos was also considered to belong to the Lep• todactylinae because of its bony mesosternum, but Lynch (1980b) reached the conclusion that its pectoral girdle with the short, wide, posteriorly bifurcate, calcified mesosternum and paired xiphisterna probably is a derived state, quite unlike that seen in the "leptodactylines sensu stricto (Adenomera, Leptodacty- lus, Lithodytes, and Vanzolinius)", which all have a long, thin, osseous meso• sternum with a spade-like xiphisternum, unique in the Leptodactylidae. Lynch (1980b) finally stated that "Barycholos seems most closely related to frogs of the discoidalis group of Eleutherodactylus". Apparently his reasoning was accepted by Laurent (in press), who considers Barycholos to belong to his Eleutherodactylinae. We concur with this view. However, this should not be construed as a statement that Phyzelaphryne and Adelophryne are derived 110 ZOOLOGISCHE MEDEDELINGEN 58 (1984) from Barycholos, as we still lack sufficient data and did not complete a detai• led study of character states in the genera concerned. Opinions about relationships of the minute frogs here discussed fluctuated considerably (see above for Barycholos), e.g. Lynch (1976) described two new species of the genus Euparkerella, for which Heyer (1977) erected the new genus Phyllonastes, whereas at the same time he described the new taxon Phy• zelaphryne miriamae. Lynch (1980b) in his turn synonymised P. miriamae with Eleutherodactylus nigrovittatus, simultaneously noting that the Vaupes River specimens referred to P. miriamae by Heyer (1977), belonged to a different species. The two species here described a.o. share a peculair character, the dis• tinctly reduced fourth finger, containing only two phalanges in Adelophryne adiastola and three in A. gutturosa. It should be stressed here that the second phalange of the fourth finger in A. gutturosa is peculiar, in that it is cubic ( 9 , LACM 44277) or at the most forms a short rectangle (cf, BM 1983. 1139), whereas in species with three phalanges in the fourth finger this second pha• lange usually forms a long rectangle. It is not clear yet whether this intraspeci- fic variation is sex-linked or not. We interpret the shape of the second phalan• ge in the fourth finger of A. gutturosa as being an intermediate stage towards losing this phalange completely, as already happened in A. adiastola. On the basis of the aforementioned skeletal character, the similarities in external morphology, in brief, the unique combination of characters presented in the generic diagnosis, we consider the two species described here to constitute a new genus, which fits well into the tribe Eleutherodactylini of the subfamily Telmatobiinae (Lynch, 1971; Dowling & Duellman, 1974-1978) or the subfa• mily Eleutherodactylinae in Laurent's (in press) terminology. At present we refrain from further speculations about the relationships because of the pauci• ty of data and specimens available. It seems useful to present a key to the small eleutherodactyline frogs with pointed or papillate toe discs and reduced fourth finger, recently described from Amazonian South America, including Eleutherodactylus nigrovittatus which has lately been confused with one of the other species. 1. Tarsal tubercle present, no vomerine teeth {Phyllonastes) — 2 — Tarsal tubercle absent, vomerine teeth present 3 2. Toe pads rounded, papillate; no supernumerary plantar tubercles Phyllonastes myrmecoides — Toe pads pointed, not papillate; obscure supernumerary plantar tubercles present Phyllonastes lochites 3. Fourth finger with two subarticular tubercles, of which the distal one may be rather indistinct; males with a fleshy ridge on the snout HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 111 Eleutherodactylus nigrovittatus — Fourth finger with one subarticular tubercle only; males without a fleshy ridge on the snout, but having a distinct subgular vocal sac 4 4. Digits round in cross-section, with well developed, salient subarticular tu• bercles, fourth finger without reduction in number or size of the phalan• ges; males with small subgular vocal sacs Phyzelaphryne miriamae — Digits flattened, with indistinct, flat subarticular tubercles, fourth finger either with reduced number of phalanges or with the second phalange dis• tinctly shortened; males with very large subgular vocal sacs (Adelophryne) — 5 5. Fourth finger with two phalanges only, free part of fourth finger less than half the length of the free part of the third finger; skin of back shagreened to granular Adelophryne adiastola — Fourth finger with three phalanges of which the second is cubic or forms a short rectangle, free part of fourth finger more than half the length of the free part of the third finger; skin of back smooth Adelophryne gutturosa ACKNOWLEDGEMENTS We wish to thank the curators of the collections who kindly loaned the material on which this study was based and/or provided working space in their laboratories during visits. Material from the following collections was used: American Museum of Natural History (AMNH), New York, U.S.A. (Dr. C. W. Myers, Dr. R. G. Zweifel); British Museum (Natural History) (BM), London, United Kingdom (Miss A. G. C. Grandison); Departamento de Zoolo- gia, Universidad de Botucatu (DZUB), Botucatu, Brazil (Dr. J. Jim); Los Angeles County Mu• seum of Natural History (LACM), Los Angeles, U.S.A. (Dr. J. W. Wright, Dr. R. L. Bezy); Mu• seum National d'Histoire Naturelle (MNHNP), Paris, France (Dr. E. G. Brygoo); Museo de Zoologia, Universidad de Sao Paulo (MZUSP), Sao Paulo, Brazil (Dr. P. E. Vanzolini); Rijksmu- seum van Natuurlijke Historie (RMNH), Leiden, The Netherlands; National Museum of Natural History (USNM), Washington, U.S.A. (Dr. W. R. Heyer, R. I. Crombie); University of Texas at Arlington, Department of Biology (UTACV), Arlington, U.S.A. (Dr. W. F. Pyburn). The X-ray photographs used for this study were kindly prepared by drs. J. P. Gasc and Mme. S. Renous of the Laboratoire d'Anatomie Comparee, Museum National d'Histoire Naturelle, Paris. We also wish to thank them for fruitful discussions on problems related to reduction of skeletal elements. Work in MZUSP by MSH was made possible through a grant of the Instituto Butantan, to partake in the " 1 ° simposio internacional sobre serpentes em geral e artropodes peconhentos" in November 1981. Work in Brazil by JL was made possible through the franco-brasilian contract CNRS/CNPq and his expedition in Amazonian Peru was funded by CNRS (RCP 316) and FNRS Suisse (requete no. 1.484-077.S.). The drawings of Adelophryne adiastola were prepared by Mrs. I. M. den Boer-van Noortwijk, those of A. gutturosa by Mr. W. C. G. Gertenaar, both of the RMNH. All other figures were made by MSH. 112 ZOOLOGISCHE MEDEDELINGEN 58 (1984) LITERATURE CITED Chapman, J. R., 1973. Climatological report of the British Roraima Expedition. In: A. N. Warren (ed.): Roraima. Report of the 1971 British Expedition to Mount Roraima in Guyana, South America: 8998. Dowling, H. G., & W. E. Duellman, 19741978. Systematic Herpetology: A synopsis of families and higher categories. — HISS Publ. Herp. 7: 1118, figs. Harding, Κ. Α., 1983. Catalogue of New World Amphibians: IXIV, 1406 Oxford, etc. Heyer, W. R., 1969. Studies on the genus Leptodactylus (Amphibia, Leptodactylidae) III. A rede finition of the genus Leptodactylus and a description of a new genus of leptodactylid frogs. — Contr. Sei. L. A. C. M. Nat. Hist. 155: 114, figs. 15, table 1. Heyer, W. R., 1973. Systematics of the marmoratus group of the frog genus Leptodactylus (Am phibia, Leptodactylidae). — Contr. Sei. L. A. C. M. Nat. Hist. 251: 150, figs. 129. Heyer, W. R., 1974. Vanzolinius, a new genus proposed for Leptodactylus discodactylus (Amphi bia, Leptodactylidae). — Proc. Biol. Soc. Wash. 87 (11): 8190, fig. 1. Heyer, W. R., 1977. Taxonomie notes on frogs from the Madeira and Purus rivers, Brasil. — Pap. Av. Zool. 31(8): 141162, figs. 14, table 1, app. 12. Hoogmoed, M. S., 1979. The Herpetofauna of the Guianan Region. In: W. E. Duellman (ed.): The South American Herpetofauna: Its origin, evolution, and dispersal. — Mus. Nat. Hist. Univ. Kansas Monogr. 7: 241279, fig. 10.1—10.13, tables 10.110.8, app. 10.1. I. G. A. C, 1977. Zonas de vida o formaciones végétales de Colombia. Memoria Explicativa sobre el Mapa Ecológico. — I. G. A. C. XIII (11): 1238, figs. 188, maps 121. Laurent, R. F. (in press). Systématique et repartition géographique. In: P. P. Grasse (ed.): Traité de Zoologie 16. Amphibiens, fasc. B. Paris. Lutz, B., 1954. Anfíbios anuros do Distrito Federal. — Mem. Inst. Osw. Cruz 52(1): 155—238, pis. IXXIX. Lynch, J. D., 1971. Evolutionary relationships, osteology, and zoogeography of leptodactyloid frogs. — Univ. Kansas Mus. Nat. Hist. Misc. Publ. 53: 1238, figs. 1131, tables 16. Lynch, J. D., 1976. Two new species of frogs of the genus Euparkerella (Amphibia: Leptodactyli dae) from Ecuador and Peru. — Herpetologica 32(1): 48—53, figs. 1—3. Lynch, J. D., 1980a. A taxonomie and distributional synopsis of the amazonian frogs of the genus Eleutherodactylus. — Am. Mus. Nov. 2696: 124, figs. 15, tables 12. Lynch, J. D., 1980b. A new species of Barycholos from Estado Goiás, Brasil (Amphibia, Anura, Leptodactylidae) with remarks on related genera. — Bull. Mus. natn. Hist, nat., Paris, (4) 2, A (1): 289302, figs. 18. Lynch, J. D., & J. Lescure, 1980. A collection of eleutherodactyline frogs from Northeastern Amazonian Peru with descriptions of two new species (Amphibia, Salientia, Leptodactylidae). — Bull. Mus. nam. Hist, nat., Paris (4) 2, A(l): 303316, figs. 14, table 1. Philcox, D., 1973. Botanical Report of the British Roraima Expedition. In: A. N. Warren (ed.): Roraima. Report of the 1971 British Expedition to Mount Roraima in Guyana, South Ameri ca: 6972. Pyburn, W. F., 1977. A new hylid frog (Amphibia, Anura, Hylidae) from the Vaupés River of Colombia with comments on related species. — J. Herpet. 11(4): 405—410, figs. 1—4. Warren, A. N., 1973. Roraima. Report of the 1971 British Expedition to Mount Roraima in Guyana, South America: 1—152, figs., maps, tables, app. HOOGMOED & LESCURE: SOUTH AMERICAN FROGS 113 Character P. miriamae E. nigrovittatus 1. subarticular tubercles fingers 1-1-2-1 1-1-2-2 2. subarticular tubercles toes 1-1-2-3-2 1-1-2-3-2 3. shape subarticular tubercles fingers salient flat 4. palmar tubercles 3 4-5 5. solar tubercles 0 0-1 6. cross-section fingers/toes round depressed, oval 7. relative length fingers/arms longer shorter very much small• only slightly smaller 8. outer metatarsal tubercle er than inner than inner metatarsal metatarsal tubercle tubercle truncate (dorsal pointed (dorsal view) 9. shape of snout view), truncate acuminate (profile) (profile) (â with shovel- shaped ridge) 10. lateral surface head vertical sloping separated from in contact with 11. subtympanic glandular ridge tympanum tympanum long transverse short transverse series, 12. vomerine teeth series, ca. 9 teeth 5-7 teeth 13. dorsal skin shagreened pustulous — smooth row of low, flat 14. upper eyelid no tubercles tubercles 15. inguinal black spot absent present Table 1. Differences between Phyzelaphryne miriamae and Eleutherodactylus nigrovittatus. Character Adelophryne adiastola Adelophryne gutturosa Phyzelaphryne miriamae UTACV BM LACM LACM MZUSP USNM Reg. no. 4940 4941 4942 4943 1983.1139 44277 44278 49894 49895 202607 202608 239363 sex 9 9 hgr. 9 9 9 N 6 6 6 6 O s-v length 13.0 13.3 13.9 13.7 14.5 13.0 8.3 20.0 15.1 20.0 19.4 14.6 O r head length 4.7 5.3 5.3 5.4 5.1 4.9 3.4 7.3 5.8 7.1 7.0 5.5 O head width 4.5 4.4 4.5 4.6 5.0 4.5 3.0 6.4 5.0 6.3 6.0 4.8 O tibia length 6.0-? 6.4-6.1 6.6-? 6.3-? 7.1-7.1 5.9-6.1 4.4-4.3 8.8-8.9 7.6-7.5 8.5-8.5 8.5-8.7 6.5- n IOD 1.4 1.4 1.7 1.4 1.6 1.8 1.3 ? ? 2.1 2.1 1.8 x m width eyelid 0.9-0.9 1.0-1.1 1.0-? 1.0-1.1 1.0-1.2 0.9-0.9 0.7-0.8 ? ? 1.4-1.5 1.4-1.6 1.3-? eye length 1.8-1.7 1.9-1.7 1.8-1.7 1.8-1.9 2.0-1.8 1.6-1.6 1.2-1.3 2.7-2.6 2.2-2.4 2.3-2.5 2.4-2.5 2.2-? tn O tymp. length 0.6-0.5 0.6-0.7 0.8-0.8 0.7-0.7 0.6-0.6 0.7-0.7 0.4-0.4 1.2-1.1 0.8-0.8 1.0-1.1 1.1-1.1 0.8-? m eye-tip snout 1.8-1.9 1.9-2.1 1.9-2.1 2.1-2.1 2.1-2.1 1.7-1.8 1.3-1.3 3.1-2.9 2.7-2.4 2.5-2.8 2.9-3.0 2.3-? a vomerine teeth 2-3? 7-8 3-3? 5-5? 5-3 3-2 ? ? ? 9-9(?) 9-9 (?) 7 m r vocal sac - large - large large - - - small - - small vocal slits + + — + + — — - + — - + a oviducts large large - 7 large 7 - m - - - - - z Table 2. Morphometric and secondary sexual characters of Adelophryne adiastola, A. gutturosa and Phyzelaphryne miriamae. Under vomerine oo teeth the question-mark indicates that these counts are not exact, but they indicate the range. Elsewhere a question-mark means that the value either could not be obtained because of technical problems, or was not recorded. + = present, - = absent, IOD = interorbital distance. All oo measurements are in mm. The DZUB specimen of P. miriamae was not measured, only identified. Euparkerella Adelophryne Phyzelaphryne Phyllonastes Eleutherodactylus character brasiliensis adiastola gutturosa miriamae myrmecoides nigrovittatus discs circumferentially — — — — + + grooved X o discs laterally — + + + — — o grooved o o m tarsal tubercle - - - - + - D vomerine teeth - + + + - + r o subarticular tubercles c 1 1 1 1 1 2 fourth finger w phalangeal formula o 2-2-3-2 2-2-3-2 2-2-3-3 2-2-3-3 2-2-3-2 2-2-3-3 c hand H > second finger much slightly much m compared to fourth 2>4 4<2 4 < 2 2 = 4 2>4 2>4 2 >n slightly skin rugose smooth shagreened finely rugose smooth O shagreened o extremely short short long moderately moderately GO fingers short long long subarticular tubercles flat, flat, flat, salient, flat, flat, fingers distinct indistinct indistinct rounded indistinct distinct Table 3. Comparison of small eleutherodactyline genera from the Amazonian area and SE Brazil with reduced fourth finger and pointed digit tips.